In modern photographic equipment, most interchangeable lenses are held in place by so-called bayonet connections, with a plurality of wings or lugs on the interchangeable lens engaging in slots on the camera, when the lens is first moved axially toward the camera and then twisted or rotated to a certain extent around the optical axis as a center. Many users find this rather cumbersome, in addition to which there is always the danger that, when a lens is applied to the camera, it will not be twisted or rotated sufficiently far to its intended completed mounted or home position.
It would be desirable, therefore, to provide a lens retaining arrangement whereby the interchangeable lens could be quickly and easily mounted on the camera by merely a straight axial motion, without any twisting or rotation. Such mounting mechanism has already been suggested, one example being disclosed in a German published application (Offenlegungsschrift) No. 2,159,152. However, the mechanism suggested in this German application is not wholly satisfactory, for various reasons.
An object of the present invention is the provision of a simple and satisfactory retaining mechanism enabling the mounting of the interchangeable lens on the camera by a simple axial movement alone, in the direction of the optical axis, without requiring any turning or twisting either of the lens or of any other part, and enabling the interchangeable lens to be simply and quickly removed from the camera likewise with a simple axial movement without any turning or twisting.
Another object is the provision of such mounting or retaining mechanism in a simple and comparatively inexpensive form, easy to manufacture, sturdy and reliable in use, and effective to hold the lens firmly in exactly the right position on the camera body, without any possibility of accidental disengagement.
Still another object is the provision of such mechanism where the latching contact between a part on the camera and a part on the lens is at least a linear contact and preferably an area contact, as distinguished from a mere point contact, thus distributing the holding pressure rather than concentrating it at one point, thereby enabling material of lower grade to be used for the contacting surfaces.